1. Field of the Invention
The present invention relates to a flexible sheath intended for transferring casings used in butchery onto a carrier tube, for sausage production.
2. Description of Related Art
The casings used in butchery are generally natural sheep, pig or cow casings. They can either be used singly, or be juxtaposed, or be overlapped. The casings are generally delivered preassembled on flexible sheaths or rigid tubular members, then transferred onto the carrier tube.
Numerous types of flexible sheaths made of plastic are currently used by butchers for transferring casings onto a tube, in particular the sheath described in French Patent No. 2,462,871 which can be withdrawn from the carrier tube by tearing along a pre-cutout of the sheath.
Such a sheath is not, however, free from drawbacks. In fact, a pre-cutout can have zones of higher strengths following an unequal perforation, which can cause a discontinuity in the movement of withdrawing the sheath, and locally cause splitting or superposition of the casings. Furthermore, when the sheath comprises a double pre-cutout (in order to facilitate manufacture of the sheath), the simultaneous breaking of the two pre-cutouts can lead to the formation of a plastic tongue which, in the event of a handling error, may cause damage to the casings, or even be carried into the sausage meat during the securing. Finally, this sheath is not reusable.
It was therefore necessary to remedy these drawbacks. Now, it has unexpectedly been found that elements otherwise known for leaktight closure of plastic packaging bags can be favourably used for transferring the casings. These elements known for the solidity of their closure allow easy and controlled opening of a flexible sheath intended for transfer onto a carrier tube.